Pulling iron

ABSTRACT

A pulling iron adapted to be partially embedded in an underground vault has a loop of steel cable wherein the legs and bight portion of the loop are coated with a polymeric plastic material. Each leg has an extension disposed at an angle with respect thereto to facilitate connection thereof to rebars. The coating on each leg is integral in one piece with a mold plate extending across the loop.

O Umted States Patent [191 [111 3,916,590

Miller Nov. 4, 1975 PULLING IRON 3,420,014 1/1969 Courtois et al. 52/125x 3,431,012 3/1969 Courtois et a]. 52/125 X [76] Inventor- Arthur Mlue"Concrete 3,562,979 2/1971 Ali-Oglu 52/125 Products, Inc., Rte. 29,Devault, Pa. 19432 Primary Examiner-J. Karl Bell [22] Filed: Dec. 19,1974 Attorney, Agent, or Firm-Seidel, Gonda & 21 Appl. No.2 534,508Gddhamme 52 U S Cl [57] ABSTRACT 1 52/125 A pulling iron adapted to bepartially embedded in an [51] Int. Cl. E04H 13/00 d d l h l f l bl h[58] Field of Search 52/125, 128, 142, 133, Y a ca e W the legs andbight port1on of the loop are coated wlth 52/124 a polymerlc plastlcmatenal. Each leg has an extension disposed at an angle with respectthereto to facilitate [56] References Cited connection thereof torebars. The coating on each leg UNITED STATES PATENTS is integral in onepiece with a mold plate extending 2,794,336 6/1957 Ballou 52/125 Xacross the 1001; 3,l24,385 3/1964 Neptune 52/125 X 3,263,378 8/1966Dorris 52 125 x 11 Clams, 4 Drawmg Figures US. Patent Nov. 4, 19753,916,590

PULLING IRON BACKGROUND Pulling irons are per se old in the art ofconcrete reinforced underground vaults. Such vaults are generally madeof two or more pieces coupled together. See FIG. 6 of Pat. No. 3,263,378wherein the pulling irons are located in or near the bottom wall of thevault. Wires to be joined within the vault are looped through the pullmgII'OI'IS.

Present pulling irons are usually zinc coated steel and weighapproximately pounds. The zinc coating is easily damaged by hooks whichengage the loop of the pulling irons and otherwise have a very limitedlifetime. The underground vaults usually have water in them so that thepulling irons in an existing vault are usually rusty.

Use of the present pulling irons as described above requires aremoveable plate on the steel forms used for casting the vault orcomponents thereof. Before the concrete vault can be stripped from theforms, the plate must be removed.

The pulling iron of the present invention is adapted to be partiallyembedded in a wall of an underground vault such as the bottom wallthereof. The pulling iron is in the form of a loop of steel cable havinglegs extending from a bight portion. Each leg has an extension disposedat an angle with respect thereto to facilitate connection of the pullingiron to a rebar.

A polymeric plastic coating is provided on each leg so as to encase thebight portion and at least a part of the legs. The coating covers allportions of the pulling iron loop adapted to be exposed when the pullingiron is partially embedded in a wall of the underground vault.

In the preferred embodiment of the present invention, a surface plate ismolded integrally with the coating on the legs of the loopvand extendsbetween the legs of the loop. The surface plate is of sufficient size sothat it may overlie the slot in a metal castirig form. The coated loopextends through the slot in the metal form while the surface plateoverlies the entire slot in said form during casting of the vault. Thesurface plate is preferably provided with projections for properlyaligning the plate with the slot in the casting form and to prevent theloop from tilting during casting of the vault.

It is an object of the present invention to provide a novel pulling ironwhich is stronger and less expensive than those utilized heretofore,while being lighter in weight and noncorrosive.

Other objects will appear hereinafter.

For the purpose of illustrating the invention, there is shown in thedrawings a form which is presently preferred; it being understood,however, that this invention is not limited to the precise arrangementsand instrumentalities shown.

FIG. 1 is a vertical sectional view through an underground vault.

FIG. 2 is a perspective view ofa pulling iron in accordance with thepresent invention.

FIG. 3 is an enlarged detail view of steel forms in which the bottomwall of the vault shown in FIG. 1 is being cast.

FIG. 4 is a partial plan view taken along the line 4-4 in FIG. 3.

Referring to the drawing in detail, wherein like numerals indicate likeelements, there is shown in FIG. 1

a concrete reinforced underground vault of a simplified constructionhaving a manhole 12 to facilitate entry thereinto. The vault 10 includesa bottom wall 14 containing one or more of the pulling irons l6partially embedded therein. A wire way or conduit 18 for wirescommunicates with the interior of the vault 10 through a vertical sidewall thereof. If desired, another conduit 20 may communicate withanother one of the side walls of the vault l0. Wires to be joined withinthe vault 10 enter the same through the conduit 18 and/or 20.

The pulling iron 16 is embedded in or near the bottom wall 14 of thevault 10. The pulling iron 16 includes a bight portion 22 from whichextends legs 24 and 26 of a steel cable. Leg 24 terminates in an angledextension 28 while leg 26 terminates in an angled extension 30. Thesteel cable is preferably a rigid cable having seven or eight strandsand which complies with ASTM Designation: A4l6-68 so as to have aminimum ultimate strength of 250,000 psi based on the nominal area ofthe strand. In a seven strand cable, there is a center wire enclosedtightly by six helically placed outer wires with a uniform pitch of notless than 12 and not more than 16 times the nominal diameter of thestrand.

The bight portion 22 and any portion of the legs 24 and 26 adapted to beexposed when the pulling iron 16 is embedded in the vault 10, areprovided with a coating 32 of polymeric plastic material. It will benoted that the coating 32 is thicker on the inside of the bight portion22. Otherwise the coating 32 is of uniform thickness. I have found asuitable thickness for coating 32 to be one-eighth of an inch.

The coating 32 may be a wide variety of polymeric plastic materialswhich are hard, rigid, strong, tough and resilient, dimensionally stableunder exposure to moisture and heat, resistant to chemicals, highstrength, and which are a substantially non-hygroscopic (have a waterabsorption of less than l%/24 hours). I prefer to use a highlycrystalline acetal copolymer sold commercially under the trademarkCelcon, having a water absorption of 0.41%[24 hours; tensile strength of10,000 psi; elongation 15%; flexural strength 14,000 psi; and shearstrength of 9,500 psi.

Due to the fact that the cable has an irregular surface, a nonrotatablecoating 32 may be applied thereto with a good bond between the cable andthe coating, The irregular surface of the cable also facilitates a goodbond with the concrete in which it is to be embedded as describedhereinafter.

The coating 32 terminates in radially outwardly directed flanges 34 and36 on the legs 24 and 26 respectively. The flanges 34 and 36 act asbarriers for any water or moisture which tends to follow the seambetween the concrete and the coating 32. The coating 32 on leg 24 ispreferably integral in one piece with the coating 32 on the leg 26 byway of a surface plate 38. Thus, coating 32 and plate 38 are molded ontothe cable at the same time. Plate 38 is provided with a plurality ofprojections such as projections 40, 42 and 44. The projections areintegral with the plate and are spaced inwardly from the periphery ofplate 38 as shown more clearly in FIG. 2. The projections have a heightof about 1% inch, a thickness of about one-eighth inch, and a widthcorresponding to the diameter of the coated loop as shown more clearlyin FIG. 4.

The components of the vault 10 are cast using metal casting formsincluding the inner form plate 46 and an outer plate form 48. Beforeconcrete 56 is poured into the space between the form plates 46 and 48,the loop of the pulling iron 16 is inserted through the slot 54 in theplate '46. The plate 38 overlies the peripheral portion on the plate 46around the slot 54. The distance between projections 40 and 44corresponds to the length of the slot so as to properly orientate theloop of the pulling iron with respect to the slot. Each of theprojections 40-44 extends through the slot 54 and maintains the loopperpendicular to the plane of the plate 46. The loop should not tiltduring the introduction of concrete 56 into the space between the formplates 46, 48.

The exposed portion of the legs 24, 26 and/or the extensions 28, 30 arerigidly connected to transverse rebars 50 and/or longitudinallyextending rebars 52. Hence, the pulling iron 16 is an integral part ofthe reinforcing steel for the vault 10. The extensions 28 and 30 neednot be angled upwardly in FIG. 4 but rather may extend horizontally inFIG. 4.

It will be noted that there is no separate plate to be removed as partof the casting forms in order to accomodate the pulling iron 16. Whenthe form plates 46, 48 are stripped, the plate 38 remains as a part ofthe vault flush with the wall of the vault except for the projections40-44 which may remain or may be removed with a grinder if desired.

While the above described polymeric plastic is preferred as the materialfor coating 32 and plate 38, other thermoplastic materials capable ofbeing injection molded may be used. For example, an acetal resin soldunder the trademark DELRIN may be used. The coating 32 has a smoothouter periphery but its inner periphery enters the crevices betweenadjacent peripheral strands of the cable so as to be non-rotatable withrespect to the cable.

Dimensions can vary depending on the size of the vault. The followingare exemplary by way of example and not by way of limitation: theincluded angle between legs 24, 26 is 52, the cable has a diameter ofone-half inch, coating 32 is one-eighth inch except for the inner sideof bight portion 22 which is one-fourth inch, plate 38 is 3/32 inch, theextensions 28, 30 are about 6 inches long and perpendicular to theirrespective legs, and plate 38 is connected to legs 24, 26 at theirmidpoint about 4 inches from bight portion 22. The included anglebetween legs 24, 26 is usually 4565.

The present invention may be embodied in other specific forms withoutdeparting from the spirit or essential attributes thereof and,accordingly, reference should be made to the appended claims, ratherthan to the foregoing specification as indicating the scope of theinvention.

I claim:

1. A pulling iron adapted to be partially embedded in an undergroundvault comprising a loop of steel strandtype cable, said loop having legsextending from a bight portion, each leg having an extension disposed atan angle with respect thereto to facilitate connection thereof torebars, said bight portion and at least a portion of each leg beingencased in a coating of polymeric plastic material, said coatingcovering all portions of said loop adapted to be exposed when the loopis partially embedded in a wall of a vault, said coating being a toughplastic material which has substantially no ab- 4 sorption with respectto water and oil, said coating being non-rotatable with respect to saidcable.

2. A pulling iron in accordance with claim 1 including a plate extendingacross said legs, said plate being integral in one piece with thecoating on said legs at a location where the legs are adapted to emergefrom a wall of a vault whereby the plate will be substantially flushwith a wall of the vault, said plate being of the same material as saidplastic material.

3. A pulling iron in accordance with claim 2 wherein said steel cableincludes a center wire enclosed tightly by at least six helically placedouter wires and has a minimum ultimate strength of at least 250,000 psi.

4. A pulling iron in accordance with claim 2 including a plurality ofprojections on one surface of said plate, said projections extendingaway from said plate toward the bight portion of said loop.

5. A pulling iron in accordance with claim 2 wherein the'coating on saidlegs terminates in a radially outwardly extending protuberance, saidplate being connected to said coating between said bight portion andsaid protuberances.

6. A pulling iron in accordance with claim 1, a concrete reinforcedvault having a bottom wall, said pulling iron being embedded in saidvault bottom wall, said loop and plate being exposed, said plate beingsubstantially flush with the surface of said bottom wall.

7. A pulling iron comprising a loop of steel strandtype cable, said loophaving legs extending from a bight portion, each leg having an extensiondisposed at an angle with respect thereto, a polymeric plastic coatingon said bight portion and on at least a substantial portion of each leg,a plate-like member extending between said legs, said plate-like memberbeing integral with and of the same material as said plastic coating,said plastic coating being a tough plastic material having a waterabsorbency of less than l%/24 hours.

8. A pulling iron in accordance with claim 7 wherein said coating onsaid bight portion and legs extends into crevices between adjacentperipheral strands of said cable to render the coating non-rotatablewith respect to said cable.

9. A pulling iron in accordance with claim 8 wherein said plasticcoating on said bight portion and legs is of substantially uniformthickness except for the inner side of the bight portion which isthicker than the remainder of the coating.

10. A pulling iron comprising a loop of metal strand cable having acenter wire enclosed tightly by a plurality of helically placed outerwires, said loop having a bight portion from which a pair of legsextends, each leg having an extension disposed at an angle with respectthereto, a polymeric plastic coating on said bight portion and extendingalong a portion of each leg, the remaining portion of each leg and eachextension being free from any coating, said coating extending intocrevices between adjacent peripheral strands of said cable so that thecoating is non-rotatable with respect to the cable.

11. A pulling iron in accordance with claim 10 including a plate-likemember integral with said coating and extending between said legs, saidmember being wider than the diameter of said coated loop.

1. A pulling iron adapted to be partially embedded in an undergroundvault comprising a loop of steel strand-type cable, said loop havinglegs extending from a bight portion, each leg having an extensiondisposed at an angle with respect thereto to facilitate connectionthereof to rebars, said bight portion and at least a portion of each legbeing encased in a coating of polymeric plastic material, said coatingcovering all portions of said loop adapted to be exposed when the loopis partially embedded in a wall of a vault, said coating being a toughplastic material which has substantially no absorption with respect towater and oil, said coating being non-rotatable with respect to saidcable.
 2. A pulling iron in accordance with claim 1 including a plateextending across said legs, said plate being integral in one piece withthe coating on said legs at a location where the legs are adapted toemerge from a wall of a vault whereby the plate will be substantiallyflush with a wall of the vault, said plate being of the same material assaid plastic material.
 3. A pulling iron in accordance with claim 2wherein said steel cable includes a center wire enclosed tightly by atleast six helically placed outer wires and has a minimum ultimatestrength of at least 250,000 psi.
 4. A pulling iron in accordance withclaim 2 including a plurality of projections on one surface of saidplate, said projections extending away from said plate toward the bightportion of said loop.
 5. A pulling irOn in accordance with claim 2wherein the coating on said legs terminates in a radially outwardlyextending protuberance, said plate being connected to said coatingbetween said bight portion and said protuberances.
 6. A pulling iron inaccordance with claim 1, a concrete reinforced vault having a bottomwall, said pulling iron being embedded in said vault bottom wall, saidloop and plate being exposed, said plate being substantially flush withthe surface of said bottom wall.
 7. A pulling iron comprising a loop ofsteel strand-type cable, said loop having legs extending from a bightportion, each leg having an extension disposed at an angle with respectthereto, a polymeric plastic coating on said bight portion and on atleast a substantial portion of each leg, a plate-like member extendingbetween said legs, said plate-like member being integral with and of thesame material as said plastic coating, said plastic coating being atough plastic material having a water absorbency of less than 1%/24hours.
 8. A pulling iron in accordance with claim 7 wherein said coatingon said bight portion and legs extends into crevices between adjacentperipheral strands of said cable to render the coating non-rotatablewith respect to said cable.
 9. A pulling iron in accordance with claim 8wherein said plastic coating on said bight portion and legs is ofsubstantially uniform thickness except for the inner side of the bightportion which is thicker than the remainder of the coating.
 10. Apulling iron comprising a loop of metal strand cable having a centerwire enclosed tightly by a plurality of helically placed outer wires,said loop having a bight portion from which a pair of legs extends, eachleg having an extension disposed at an angle with respect thereto, apolymeric plastic coating on said bight portion and extending along aportion of each leg, the remaining portion of each leg and eachextension being free from any coating, said coating extending intocrevices between adjacent peripheral strands of said cable so that thecoating is non-rotatable with respect to the cable.
 11. A pulling ironin accordance with claim 10 including a plate-like member integral withsaid coating and extending between said legs, said member being widerthan the diameter of said coated loop.